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Identifying Infrastructure-Based Motorcycle-Crash Countermeasures: Phase I Final Workshop Finding ReportPUBLICATION NO. FHWA-HRT-18-062 SEPTEMBER 2018

Research, Development, and TechnologyTurner-Fairbank Highway Research Center6300 Georgetown PikeMcLean, VA 22101-2296

FOREWORD

To date, efforts to address motorcycle crashes have largely focused on driver-behavior issues.

Infrastructure-based motorcycle-crash countermeasures can significantly improve motorcycle-

rider safety; however, identifying effective countermeasures can be challenging. Research is

needed to identify infrastructure-based countermeasures that could be used to reduce the

frequency and consequences of injurious and fatal motorcycle crashes.

To respond to this need, the Federal Highway Administration sponsored a project to identify

three to five infrastructure-based motorcycle-crash countermeasures to consider for future

research. A workshop, Identifying Infrastructure-Based Motorcycle-Crash Countermeasures, was

conducted to develop a list of prioritized infrastructure-based motorcycle-crash countermeasures.

This report presents the workshop overview and results. This report will be of interest to

engineers, academics, researchers, industry partners, and riders involved in the design,

construction, installation, and testing of infrastructure-based countermeasures to address

motorcycle crashes.

James S. Pol, P.E., PMP

Acting Director, Office of Safety Research

and Development

Notice

This document is disseminated under the sponsorship of the U.S. Department of Transportation

(USDOT) in the interest of information exchange. The U.S. Government assumes no liability for

the use of the information contained in this document.

The U.S. Government does not endorse products or manufacturers. Trademarks or

manufacturers’ names appear in this report only because they are considered essential to the

objective of the document.

Quality Assurance Statement

The Federal Highway Administration (FHWA) provides high-quality information to serve

Government, industry, and the public in a manner that promotes public understanding. Standards

and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its

information. FHWA periodically reviews quality issues and adjusts its programs and processes to

ensure continuous quality improvement.

TECHNICAL DOCUMENTATION PAGE

1. Report No.

FHWA-HRT-18-062

2. Government Accession No. 3. Recipient’s Catalog No.

4. Title and Subtitle

Identifying Infrastructure-Based Motorcycle-Crash Countermeasures:

Phase I

Final Workshop Finding Report

5. Report Date

September 2018

6. Performing Organization Code

7. Author(s)

A. Trueblood (ORCID: 0000-0002-1404-347X), M. Manser (ORCID:

0000-0003-4510-0569), E. Shipp (ORCID: 0000-0002-4034-8031), and

C. Havemann (ORCID: 0000-0001-8029-1159)

8. Performing Organization Report

No.

9. Performing Organization Name and Address

Texas A&M Transportation Institute

Texas A&M University System

2929 Research Parkway

College Station, TX 77843

10. Work Unit No.

11. Contract or Grant No.

DTFH6116D00039

12. Sponsoring Agency Name and Address

Federal Highway Administration

Office of Safety Research and Development

6300 Georgetown Pike

McLean, VA 22101

13. Type of Report and Period

Covered

Final Report; August 2018

14. Sponsoring Agency Code

HRDS-20

15. Supplementary Notes

This study was part of the project Identifying Infrastructure-Based Motorcycle-Crash Countermeasures: Phase I,

which was performed with the cooperation and participation of Yusuf Mohamedshah (HRDS-20; ORCID 0000-

0003-0105-5559) of the Federal Highway Administration Office of Safety Research and Development.

16. Abstract

In 2017, the Federal Highway Administration sponsored a project to identify three to five infrastructure-based

motorcycle-crash countermeasures to consider for future research. To develop a list of prioritized infrastructure-

based motorcycle-crash countermeasures, a workshop titled Identifying Infrastructure-Based Motorcycle-Crash

Countermeasures was conducted on February 13, 2018, in Arlington, VA. The workshop opened with an

introduction that provided participants with results from the prior tasks of the project, including an analysis of

the data from the Motorcycle Crash Causation Study and a literature review. Participants discussed

countermeasures from the prior tasks as well as the addition of other countermeasures. At the end of the

workshop, a number of participants voted for their preferred countermeasures to develop a list of prioritized

countermeasures. This report presents the workshop overview and results.

17. Key Words

Motorcycle safety, motorcyclist fatalities,

infrastructure-based countermeasure

18. Distribution Statement

No restrictions. This document is available to the public

through the National Technical Information Service,

Springfield, VA 22161.

http://www.ntis.gov

19. Security Classif. (of this report)

Unclassified

20. Security Classif. (of this page)

Unclassified

21. No. of Pages

23

22. Price

N/A

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized.

ii

SI* (MODERN METRIC) CONVERSION FACTORS APPROXIMATE CONVERSIONS TO SI UNITS

Symbol When You Know Multiply By To Find Symbol

LENGTH in inches 25.4 millimeters mm ft feet 0.305 meters m

yd yards 0.914 meters m mi miles 1.61 kilometers km

AREA in

2square inches 645.2 square millimeters mm

2

ft2

square feet 0.093 square meters m2

yd2

square yard 0.836 square meters m2

ac acres 0.405 hectares ha

mi2

square miles 2.59 square kilometers km2

VOLUME fl oz fluid ounces 29.57 milliliters mL

gal gallons 3.785 liters L ft

3 cubic feet 0.028 cubic meters m

3

yd3

cubic yards 0.765 cubic meters m3

NOTE: volumes greater than 1000 L shall be shown in m3

MASS oz ounces 28.35 grams g

lb pounds 0.454 kilograms kg

T short tons (2000 lb) 0.907 megagrams (or "metric ton") Mg (or "t")

TEMPERATURE (exact degrees) oF Fahrenheit 5 (F-32)/9 Celsius

oC

or (F-32)/1.8

ILLUMINATION fc foot-candles 10.76 lux lx fl foot-Lamberts 3.426 candela/m

2 cd/m

2

FORCE and PRESSURE or STRESS lbf poundforce 4.45 newtons N lbf/in

2poundforce per square inch 6.89 kilopascals kPa

APPROXIMATE CONVERSIONS FROM SI UNITS

Symbol When You Know Multiply By To Find Symbol

LENGTHmm millimeters 0.039 inches in

m meters 3.28 feet ft

m meters 1.09 yards yd

km kilometers 0.621 miles mi

AREA mm

2 square millimeters 0.0016 square inches in

2

m2 square meters 10.764 square feet ft

2

m2 square meters 1.195 square yards yd

2

ha hectares 2.47 acres ac

km2

square kilometers 0.386 square miles mi2

VOLUME mL milliliters 0.034 fluid ounces fl oz

L liters 0.264 gallons gal m

3 cubic meters 35.314 cubic feet ft

3

m3

cubic meters 1.307 cubic yards yd3

MASS g grams 0.035 ounces oz

kg kilograms 2.202 pounds lbMg (or "t") megagrams (or "metric ton") 1.103 short tons (2000 lb) T

TEMPERATURE (exact degrees) oC Celsius 1.8C+32 Fahrenheit

oF

ILLUMINATION lx lux 0.0929 foot-candles fc

cd/m2

candela/m2

0.2919 foot-Lamberts fl

FORCE and PRESSURE or STRESS N newtons 0.225 poundforce lbf

kPa kilopascals 0.145 poundforce per square inch lbf/in2

*SI is the symbol for th International System of Units. Appropriate rounding should be made to comply with Section 4 of ASTM E380. e

(Revised March 2003)

iii

TABLE OF CONTENTS

CHAPTER 1. INTRODUCTION ................................................................................................ 1

CHAPTER 2. WELCOMING REMARKS, WORKSHOP OBJECTIVES, AND

FHWA PERSPECTIVE ............................................................................................................... 3 ATTENDEE INTRODUCTIONS ........................................................................................... 3 REVIEW OF THE PROJECT, PREWORKSHOP MEETINGS, AND

WORKSHOP GOALS ....................................................................................................... 3

CHAPTER 3. SUMMARY ........................................................................................................... 5 REVIEW OF COUNTERMEASURES AND IDENTIFICATION OF

COUNTERMEASURE-IMPLEMENTATION BARRIERS ......................................... 5

SUMMARY OF THE REVIEW OF THE MCCS DATABASE ANALYSIS ..................... 5 UPDATE STAKEHOLDER COUNTERMEASURE PRIORITIZATION ........................ 6 IDENTIFICATION OF BARRIERS TO IMPLEMENTATION ........................................ 9 UPDATING THE LIST OF MCCS DATABASE QUESTIONS ....................................... 10

UPDATING THE MAPPING BETWEEN COUNTERMEASURES AND THE

MCCS DATABASE QUESTIONS.................................................................................. 11

SUMMARY OF WORKSHOP EVALUATION AND FINAL INSTRUCTIONS

FOR STAKEHOLDERS .................................................................................................. 13 WORKSHOP EVALUATION RESULTS ........................................................................... 13

FHWA-RECOMMENDED RANKING ............................................................................... 15

REFERENCES ............................................................................................................................ 17

iv

LIST OF TABLES

Table 1. List of countermeasures for prioritization ........................................................................ 7

Table 2. Ranking results of countermeasure prioritization ............................................................. 8 Table 3. Workshop evaluation results ........................................................................................... 14 Table 4. Results of FHWA countermeasure prioritization ranking .............................................. 16

v

LIST OF ABBREVIATIONS

FHWA Federal Highway Administration

ITS intelligent transportation system

MCCS Motorcycle Crash Causation Study

MUTCD Manual on Uniform Traffic Control Devices

NASS GES National Automotive Sampling System General Estimates System

1

CHAPTER 1. INTRODUCTION

In 2017, the Federal Highway Administration (FHWA) sponsored a research project to identify

three to five infrastructure-based motorcycle-crash countermeasures to consider for future

research. The first project within task B was to conduct a literature review to identify the range

of infrastructure-based motorcycle-crash countermeasures that are currently deployed or could be

deployed to lessen motorcycle-crash risks, including mitigating injuries and reducing fatalities.

The second project activity within task B consisted of an indepth analysis of the Motorcycle

Crash Causation Study (MCCS) database to determine what infrastructure-based motorcycle-

crash countermeasures, if implemented on a wide scale, could address the greatest number of

motorcycle crashes.(1) The results of both activities within task B provided critical information

regarding available infrastructure-based motorcycle-crash countermeasures and crash analyses to

a multidisciplinary group of motorcycle stakeholders. Using this information, the stakeholders

were asked to prioritize the list of countermeasures to consider for further research.

To refine the prioritization of infrastructure-based motorcycle-crash countermeasures, a

workshop was conducted on February 13, 2018, in Arlington, VA, to solicit input from key

stakeholders. This activity was task C of the project.

This report is an overview of the workshop and documents its results and conclusions. The

workshop was a 4-h meeting to solicit input from key stakeholders on the proposed

countermeasures, including their perceptions of which to consider for further research. The

workshop began with an introduction and project overview by the FHWA project Task Order

Contracting Officer’s Representative, an introduction by the FHWA Office of Safety Research

and Development Director, and introductions by key stakeholders who joined the meeting in

person and by Web-conference platform. An overview of the project and workshop activities and

goals was followed by a presentation of the literature review and a presentation of the MCCS

database-analysis results. The key stakeholders then discussed the identified countermeasures

and conducted the countermeasure prioritization activity. The final segment of the workshop

consisted of a presentation of the finalized countermeasure prioritization as well as an evaluation

of the workshop by the key stakeholders in attendance. Within 1 mo after the conclusion of the

workshop, the FHWA project staff reviewed the stakeholder-prioritized list and established a

final prioritization.

This report also summarizes the workshop activities and includes a list of key questions that

could be answered using the MCCS database as well as a logical mapping between the questions

and the highest priority countermeasures. Collectively, the prioritization activity conducted

during the workshop provided a list of infrastructure-based motorcycle-crash countermeasures to

consider for future research.

3

CHAPTER 2. WELCOMING REMARKS, WORKSHOP OBJECTIVES, AND FHWA

PERSPECTIVE

The workshop began with welcoming remarks from Mr. Yusuf Mohamedshah, Research

Highway Safety Specialist at FHWA, and Ms. Monique Evans, former Director of the Office of

Safety Research and Development at FHWA. Their introductions included the following:

• A welcoming for all attendees.

• An explanation that the workshop was part of a deliverable for an FHWA-funded project.

• An introduction to the MCCS and its relation to the workshop.

• A discussion of the potential for the workshop results to inform future research.

ATTENDEE INTRODUCTIONS

Following the introductions by Mr. Mohamedshah and Ms. Evans, attendees introduced

themselves. Attendees included broad representation from motorcycle manufacturers, research

institutes, academic institutions, Federal Government, private companies, and engineering and

safety consultants. In addition, a majority of the attendees were active motorcycle riders.

REVIEW OF THE PROJECT, PREWORKSHOP MEETINGS, AND WORKSHOP

GOALS

A brief overview of the workshop agenda and documents in the attendee folders was provided.

Next, an overview of the project goal, which was to identify three to five infrastructure-based

motorcycle-crash countermeasures to consider for future research, was provided. To reach this

goal, the project outlined the following tasks:

• Analyze the MCCS database to identify crash-causation factors that could be addressed

by infrastructure-based motorcycle-crash countermeasures.

• Review literature of infrastructure-based motorcycle-crash countermeasures.

• Conduct a preworkshop meeting to narrow the countermeasures being considered.

• Conduct a workshop to identify three to five countermeasures to consider for future

research.

Attendees who agreed to participate in the workshop also took part in the preworkshop meetings

on February 2 or February 5, 2018. The goals of the preworkshop meeting were as follows:

• Review the MCCS database analysis and the results of the analysis.

• Review the infrastructure-based motorcycle-crash countermeasures identified in the

literature review.

4

• Describe the rationale for prioritizing the list of countermeasures.

• Conduct an initial prioritization of the countermeasures to arrive at a list of 10 for an

indepth discussion during the workshop.

The goals of the workshop were as follows:

• Discuss and reprioritize the top 10 infrastructure-based motorcycle-crash

countermeasures identified during the preworkshop meeting.

• Prioritize a list of MCCS database questions.

• Link the prioritized countermeasures with the MCCS questions.

5

CHAPTER 3. SUMMARY

REVIEW OF COUNTERMEASURES AND IDENTIFICATION OF

COUNTERMEASURE-IMPLEMENTATION BARRIERS

The following list contains the top 10 countermeasures prioritized in the preworkshop. The items

appear in order of rank and include the identification number in parentheses:

1. Guardrail continuous-protection system (5.1).

2. Pavement-condition repair (2.3).

3. High-friction surface treatment (2.1).

4. In-curve warning signs (5.7).

5. Lighting (1.6).

6. Remove roadside trees and poles (5.10).

7. Signals (1.4).

8. Punctual energy absorber (5.3).

9. Limited-sight-distance warning signs (1.2).

10. Prohibitive signs (1.3).

Attendees raised the notion that the list of 10 countermeasures was diverse, but none of the

countermeasures would prevent a crash or help a rider survive a crash. This idea resulted in a

group discussion of what countermeasures should be included in the prioritization activity.

Attendees agreed that it is always more desirable to prevent a crash than to mitigate a fatality or

injury after a crash. The list of countermeasures from the preworkshop prioritization activity

focused on both crash mitigation and prevention, whereas countermeasures identified in the

MCCS database analysis focused primarily on crash prevention. After a detailed discussion of

the crash-prevention and crash-mitigation approaches, attendees had two recommendations: that

the remainder of the workshop discussion be focused on the top eight countermeasures identified

in the previous MCCS analysis and that these countermeasures serve as the core list for the

prioritization task with the option to include additional countermeasures identified in the

literature review as needed.

Researchers agreed that the approach attendees recommended was appropriate, but it

necessitated a significant modification to the workshop agenda. If time did not permit, it was

allowable to not pursue prioritizing the list of MCCS database questions and linking the

prioritized countermeasures with the MCCS questions. The discussion about identifying barriers

to countermeasure implementation concluded early to ensure sufficient time to review of the

MCCS database analysis.

SUMMARY OF THE REVIEW OF THE MCCS DATABASE ANALYSIS

The review of the MCCS database analysis began with a short description of the MCCS. The

purpose of the MCCS was to update the Hurt Report, which was used to collect data in the late

1970s.(1,2) In contrast, the MCCS data were collected from 2011 to 2016.(1) Similar to the Hurt

Report, the MCCS data represented motorcycle crashes that occurred in Orange County, CA.(1)

The MCCS database includes information on 351 motorcycle crashes and 702 motorcycle-crash

6

control cases.(1) The three main components of the MCCS analysis included completing the

following:

• Determining how well the MCCS data represented motorcycle crashes at the national

level.

• Identifying infrastructure-based motorcycle-crash countermeasures that could address the

major crash categories observed in the MCCS data.

• Estimating the potential benefit of implementing those infrastructure-based motorcycle-

crash countermeasures at the national level.

Eight countermeasures that could address at least 500 motorcycle crashes per yr were identified

from the MCCS analysis. These countermeasures included the following:

• Improving sight distance for intersections.

• Improving sight distance for nonintersections.

• Installing no-left-turn signs.

• Installing retroreflective striping.

• Installing warning signs for intersections ahead and for merging/oncoming traffic.

• Installing stop signs.

• Installing curve-speed warning signs.

Researchers then discussed the benefits of the MCCS database. These benefits included the fact

that the MCCS database is a rich source of information that contains structured data, narratives,

photographs, and diagrams. The MCCS database is unique in that it contains extensive data on

infrastructure-related factors at the time of the crash; however, a limitation of the database is that

the data represent a small geographic area (Orange County, CA), which may not be

representative of the entire United States. Researchers addressed this limitation by calibrating the

MCCS database so the data more closely matched the crash distribution in the National

Automotive Sampling System General Estimates System (NASS GES) dataset.(3) Due to the

limited sample, the analysis may have missed infrastructure-based motorcycle-crash

countermeasures that were important regionally or nationally. An additional limitation was that

crashes from the MCCS database could not be mapped appropriately to the NASS GES database

to fully explore the potential benefit of some countermeasures (e.g., ensuring proper cross slope,

side of roadway parking, and retrofit concrete barrier).

UPDATE STAKEHOLDER COUNTERMEASURE PRIORITIZATION

Researchers then led a group discussion of the eight countermeasures from the MCCS analysis.

The group discussed adding countermeasures as well as any previously unidentified

countermeasures to this list from the literature review. Attendees added the following

countermeasures:

• Pavement-condition repair (2.3).

• High-friction surface treatment (2.1).

• Textured pavement markings (2.2).

7

• Positive guidance in a work zone (5.11).

• Pavement-change warning signs (2.6).

• Guardrail continuous-protection system (5.1).

• Retrofit concrete barrier (5.2).

Attendees discussed and combined similar countermeasures. First, they combined high-friction

surface treatment (2.1) and textured pavement markings (2.2). Second, attendees combined

guardrail continuous-protection system (5.1) and retrofit concrete barrier (5.2) into a general

category titled “barrier treatments for motorcycles.” Table 1 lists the countermeasures included

in the prioritization activity.

Table 1. List of countermeasures for prioritization.

Countermeasure

Number

Countermeasures Identified in

the MCCS Database Analysis

Countermeasures Identified in the

Review of Literature

1.2 Sight distance—intersection;

sight distance—segment

Limited-sight-distance warning signs

1.3 Stop sign; no-left-turn sign Prohibitive signs

1.4 New signal with protected turn Signals

1.5 Warning intersection/driveway-

ahead sign

Intersection/merging traffic warning

signs

2.1; 2.2 — High-friction surface treatment;

textured pavement markings

2.3 — Pavement-condition repair

2.6 — Pavement-change warning signs

3.1 Sight distance—intersection;

sight distance—segment

Design for motorcycle sight distance

5.1; 5.2 — Guardrail continuous-protection

system; retrofit concrete barrier

5.5 Curve-speed warning sign Curve-speed warning

5.8 Retroreflective striping Pavement markings

5.11 — Positive guidance in a work zone —No countermeasure identified in the MCCS database analysis.

In addition to finalizing the list for prioritization, the group discussed how to weight the

countermeasures, such as by cost, number and rate of crashes reduced, implementation cost and

timeline, and number of lives saved, to name a few. However, based on the discussion, it was

clear that each attendee had a unique opinion, and therefore, they were instructed to weight

according to personal preference.

Eligible attendees were instructed to vote using an online voting platform. The poll asked

attendees to “Please rank the top motorcycle safety infrastructure-based countermeasures

identified from the MCCS analysis and our discussion today from top (most preferred) to bottom

(least preferred).” To vote, attendees selected a countermeasure and moved it higher or lower in

the list. The online voting platform automatically assigned the highest ranked countermeasure a

score of 1 and the lowest ranked countermeasure a score of 12 and created a final list by

averaging the participant scores for each countermeasure. Table 2 displays the ranking results.

8

Table 2. Ranking results of countermeasure prioritization.

Final

Rank

Average

Rank

Score Countermeasure Alignment to MCCS Analysis

1 4.63 High-friction surface treatment

(2.1); textured pavement

markings (2.2)

—

2 4.94 Pavement-condition repair

(2.3)

—

3 5.56 Limited-sight-distance warning

signs (1.2)

Sight distance—segment;

sight distance—intersection

4 6.31 Pavement-change warning sign

(2.6)

—

5 6.34 Design for motorcycle sight

distance (3.1)


sight distance—intersection

5 6.34 Curve-speed warning (5.5) Curve-speed warning signs

6 6.44 Guardrail continuous-

protection system (5.1);

retrofit concrete barrier (5.2)

—

7 6.82 Positive guidance in a work

zone (5.11)

—

8 7.13 Pavement markings (5.8) Retroreflective striping

9 7.50 Signals (1.4) New signal with protected turn cycle

10 7.88 Intersection/merging traffic

warning signs (1.5)

Warning intersections/driveway-

ahead sign

11 8.07 Prohibitive signs (1.3) Stop sign;

no-left-turn sign —No countermeasure aligned with the MCCS data analysis.

Workshop attendees also discussed several other motorcycle-related safety issues and crash

countermeasures to consider for future research, including the following:

• As improvements to intelligent transportation systems (ITSs) are made, attendees agreed

on the need for further research regarding ITSs to better understand their impact on

motorcycle crashes. For example, what is the impact of red-light-violation warning

systems on motorcycle-crash rates?

• Attendees disagreed on whether ITS implementation in the near future was realistic. They

agreed other countermeasures should be pursued over ITS. However, attendees agreed

that, as ITS improves over time, there is real potential for this countermeasure to reduce

motorcycle crashes.

• Attendees agreed on the need for research regarding the impact of crack sealing (i.e., tar

snakes), including the impact on road surface and overapplication, as well as research

regarding adding material, such as sand, to the tar to increase the friction coefficient of

the crack sealant.

9

• Attendees indicated there was a need for research regarding the impact of warning signs

on motorcycle-crash rates, specifically focusing on the impact of riders’ speed on the

propensity of crashes.

• Attendees agreed on a need for future research regarding work-zone signs. Attendees

were concerned about the potential effectiveness of work-zone signs and agreed that

examination into their basic effectiveness would be warranted. In addition, attendees

thought work-zone crashes may be overrepresented in certain geographical areas and felt

an important topic to explore is where work zones are an issue.

• Attendees discussed the need for future research on the effectiveness of guardrails

relative to rider safety. Attendees also agreed on the need for future research regarding

environmental impacts of continuous guardrails, including limiting animals’ ability to

move beyond the barrier and off the road, thus remaining a risk to riders.

A primary workshop goal was to provide FHWA a list of three to five countermeasures to

consider for future research to improve motorcyclist safety. The countermeasure prioritization

task allowed experts in motorcycle safety to rank a list of infrastructure-based motorcycle-crash

countermeasures. The five highest ranked countermeasures were as follows:

1. High-friction surface treatment (2.1) and textured pavement markings (2.2).

2. Pavement-condition repair (2.3).

3. Limited-sight-distance warning signs (1.2).

4. Pavement-change warning signs (2.6).

5. Designing for motorcycle sight distance (3.1).

A potential limitation discussed by workshop attendees is the ability to design and implement a

single study to evaluate each countermeasure. This is particularly true of the first

countermeasure, which contains two uniquely diverse approaches for improving friction that may

require two different evaluation approaches. In addition, the second countermeasure addresses

the general concept of improving roadway conditions through repairs, but there will likely be

significant challenges when designing a single study to address the wide range of possible

repairs.

IDENTIFICATION OF BARRIERS TO IMPLEMENTATION

At the onset of the workshop, researchers indicated the need to identify any barriers that would

inhibit countermeasure implementation. Throughout the workshop and particularly during the

countermeasure discussion, attendees identified several implementation barriers for FHWA to

consider including the following:

• The cost of implementation for any countermeasure, including the cost of installation and

long-term maintenance.

• The time required for implementation.

10

• An agency’s willingness to install infrastructure-based countermeasures when

motorcycles only account for a small percentage of road users and injuries/fatalities.

• A need to know the impact on both nonmotorcycle road users and motorcyclists.

Attendees also identified specific implementation barriers for some countermeasures, which

included the following:

• Guardrail continuous-protection system.

o The best solution is to implement guardrails at all possible locations but doing so is

not feasible. The issue is prioritizing locations for guardrail installation so the

locations with the greatest risk are addressed. Closely related to this issue is the

notion that agencies may be found liable if a motorcycle crash occurs on a curve

without a guardrail despite an analysis that indicated no need for a guardrail.

o Environmental problems associated with continuous guardrails, such as animal

crossings, are important factors to consider.

o Changes to guardrails, such as adding a rub rail, will result in the guardrail needing to

be retested, which would most likely be resisted.

• Warning-sign placards.

o Some Professional Transportation Operations Engineers (an Institute of

Transportation Engineers certification) may resist installing placards (e.g., 18 by 18

inches) warning motorcycle riders of a hazard ahead unique to motorcycles (e.g., a

warning for grooved pavement). Resistance may be because the placard denotes a

particular motorized vehicle that the Manual on Uniform Traffic Control Devices

(MUTCD) deems unusual.(4) However, graphics of vehicles (e.g., commercial trucks,

firetrucks, tractors) do appear in the MUTCD. Attendees noted that warning-sign

placards are employed in European countries.

UPDATING THE LIST OF MCCS DATABASE QUESTIONS

Due to reorganizing the agenda, prioritization activity, and extended group discussion about

countermeasures, researchers and FHWA staff decided not to enlist the help of attendees to

update the list of MCCS database questions during the workshop. Instead, researchers met after

the workshop and generated a list of MCCS database questions that included the following:

• Which infrastructure-based countermeasures should be examined in combination?

• For combinations of infrastructure-based countermeasures, is the order of implementation

potentially important?

• Does the ranking of infrastructure-based countermeasures differ for crash prevention

versus improvement of injury severity?

• Does the ranking of infrastructure-based countermeasures differ for scooters and mopeds

versus motorcycles?

11

• Does the ranking of infrastructure-based countermeasures differ for single-motorcycle

crashes versus multivehicle crashes?

• What pavement markings, other than retroreflective striping, could reduce crashes or

their severity?

• How do crash frequency and severity differ regarding improving sight distance of the

motorcyclist versus improving sight distance of vehicle drivers so they can more readily

see the motorcycle and rider?

• Are there infrastructure-based countermeasures that may be especially effective in certain

geographic areas or areas with specific roadway characteristics where impaired or

distracted motorcycle crashes are common?

• What injury diagnoses are associated with each infrastructure-based countermeasure?

• Which infrastructure-based countermeasures are not a top concern in the MCCS database

but are important from a national or regional perspective based on additional analysis of

the NASS GES database and possibly other datasets.

UPDATING THE MAPPING BETWEEN COUNTERMEASURES AND THE MCCS

DATABASE QUESTIONS

Due to reorganizing the agenda, prioritization activity, and extended group discussion of the

countermeasures, researchers decided not to pursue mapping the countermeasures to the MCCS

database questions during the meeting. Instead, researchers met after the workshop and mapped

the MCCS database questions to each of the five highest rated countermeasures. The mapping

results are as follows:

• High-friction surface treatment (2.1); textured pavement markings (2.2):

o Which infrastructure countermeasures should be examined in combination?

o For combinations of infrastructure-based countermeasures, is the order of

implementation potentially important?

o Are there infrastructure-based countermeasures that may be especially effective in

certain geographic areas or areas with specific roadway characteristics where

impaired or distracted motorcycle crashes are common?

o What injury diagnoses are associated with each infrastructure-based countermeasure?

o What pavement markings, other than retroreflective striping, could reduce motorcycle

crashes or their severity?

• Pavement-condition repair (2.3):

o Which infrastructure-based countermeasures should be examined in combination?

12







• Limited-sight-distance warning signs (1.2); sight distance—segment; sight distance—

intersection:








o How do crash frequency and severity differ regarding improving sight distance of the

motorcyclist versus improving sight distance of vehicle drivers so they can more

readily see the motorcycle and rider?

• Pavement-change warning sign (2.6):








• Design for motorcycle sight distance (3.1); sight distance—segment; sight distance—

intersection:




13





o How do crash frequency and severity differ regarding improving sight distance of the

motorcyclist versus improving sight distance of vehicle drivers so they can more

readily see the motorcycle and rider?

• Curve-speed warning (5.5); curve-speed warning signs:








SUMMARY OF WORKSHOP EVALUATION AND FINAL INSTRUCTIONS FOR

STAKEHOLDERS

The workshop concluded with a summary of the review and an update of the stakeholder

countermeasure prioritization. Attendees were invited to discuss their impressions of the

prioritization. They generally agreed on the prioritization with the exception of one attendee,

who was surprised that the countermeasure pavement markings (5.8) was not included in the

final ranking (see table 4) because, in the attendee’s opinion, this particular infrastructure-based

motorcycle-crash countermeasure could be deployed broadly and have a significant impact on

reducing motorcycle crashes.

Once the discussion of countermeasures ended, researchers thanked all attendees for

participating in the workshop. Traveling attendees were given a reminder to complete all travel

documents required for reimbursement. In addition, workshop attendees who voted in the

prioritization activity were asked to complete either a paper or electronic evaluation depending

on their mode of participation.

WORKSHOP EVALUATION RESULTS

Attendees who participated in the prioritization activity completed a workshop evaluation. In-

person attendees used a paper evaluation form, and Internet-conferencing attendees used an

online survey.

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Overall, the workshop received positive feedback, as evidenced by the following ratings (where

n indicates the number of attendee responses):

• 38.46 percent (n = 5) ranked the overall workshop as excellent.

• 46.15 percent (n = 6) ranked the overall workshop as very good.

• 15.38 percent (n = 2) ranked the overall workshop as good.

Table 3 provides a summary of the evaluation results.

Table 3. Workshop evaluation results.

Evaluation Items

Strongly

Agree Agree Neutral Disagree

Strongly

Disagree

The premeeting

webinar was

beneficial.

71.43%

(n = 10)

28.57%

(n = 4)

0.00%

(n = 0)

0.00%

(n = 0)

0.00%

(n = 0)

The preprioritization

voting was easy to

use.

73.33%

(n = 11)

26.67%

(n = 4)

0.00%

(n = 0)

0.00%

(n = 0)

0.00%

(n = 0)

The workshop was

well organized.

33.33%

(n = 5)

46.67%

(n = 7)

13.33%

(n = 2)

0.00%

(n = 0)

0.00%

(n = 0)

The goals of the

workshop were clearly

stated.

26.67%

(n = 4)

53.33%

(n = 8)

13.33%

(n = 2)

6.67%

(n = 1)

0.00%

(n = 0)

The workshop goals

were met.

33.33%

(n = 5)

60.00%

(n = 9)

6.67%

(n = 1)

0.00%

(n = 0)

0.00%

(n = 0)

The agenda for the

meeting was followed.

26.67%

(n = 4)

40.00%

(n = 6)

26.67%

(n = 4)

6.67%

(n = 1)

0.00%

(n = 0)

The facilities (e.g.,

meeting room, Internet

conferencing) were

appropriate.

42.86%

(n = 6)

50.00%

(n = 7)

7.14%

(n = 1)

0.00%

(n = 0)

0.00%

(n = 0)

The workshop met

your expectations.

46.67%

(n = 7)

46.67%

(n = 7)

6.67%

(n = 1)

0.00%

(n = 0)

0.00%

(n = 0)

The countermeasure

prioritization was well

organized.

40.00%

(n = 6)

53.33%

(n = 8)

6.67%

(n = 1)

0.00%

(n = 0)

0.00%

(n = 0)

The countermeasure

prioritization was fair.

53.33%

(n = 8)

40.00%

(n = 6)

0.00%

(n = 0)

6.67%

(n = 1)

0.00%

(n = 0)

Attendees also responded to the open-ended questions very positively. When asked what they

liked best or found most useful about the workshop, attendees expressed positive feedback about

the following:

• The group of experts brought in for the workshop.

• The enthusiasm of the group.

• The easiness and thoroughness of participation and discussion.

15

• The well-organized delivery of information.

• The ability to share information on motorcycle safety.

Attendees enjoyed their interactions with the staff who hosted and organized the workshop.

As indicated in their responses, what attendees least liked or found less useful included the

following:

• Articulation of workshop goals.

• Articulation of the end goal.

• Difficulty in keeping Internet-conferencing attendees focused on the end goal.

• Too much focus on the engineering side of infrastructure-based countermeasures and not

enough focus on the data analysis.

Attendees commented negatively on the technical issues experienced at the start of the

workshop, which were resolved by using a different phone microphone. Once resolved, attendees

commented that the reorganization of the workshop was for the better because it facilitated

attendees’ comprehension and then rank the infrastructure-based motorcycle-crash

countermeasures. It is clear that the changes to the agenda that occurred early on in the workshop

negatively impacted the workshop organization, and such changes should have been better

articulated.

When attendees were asked if they had any other comments or suggestions, they recommended

the following:

• Using specific criteria for ranking countermeasures.

• Recording unrelated or off comments per topic and addressing these at a later time.

• Seeing a more diverse audience of attendees from the highway industry.

FHWA-RECOMMENDED RANKING

After the workshop conclusion, researchers provided the results of the countermeasure

prioritization ranking to FHWA. Using an internal process, FHWA reviewed and modified the

ranking. This activity resulted in the ranking of five countermeasures from highest to lowest with

the highest countermeasure indicative of those to consider for future research. Table 4 displays

these results.

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Table 4. Results of FHWA countermeasure prioritization ranking.

FHWA

Ranking

Workshop

Ranking

Average

Rank

Score Countermeasure

Alignment to MCCS

Analysis

1 1 4.63 High-friction surface

treatment (2.1);

textured pavement

markings (2.2)

—

2 3 5.56 Limited-sight-distance

warning signs (1.2)


Sight distance—intersection

3 4 6.31 Pavement-change

warning sign (2.6)

—

4 5 6.34 Curve-speed warning

(5.5)

Curve-speed warning signs

5 11 8.07 Prohibitive signs (1.3) Stop sign;

no-left-turn sign —No countermeasure aligned with the MCCS database analysis.

17

REFERENCES

1. Federal Highway Administration. (2018). “Motorcycle Crash Causation Study.” (website)

Federal Highway Administration, Washington, DC. Available online:

https://www.fhwa.dot.gov/research/tfhrc/projects/safety/motorcycles/mccs/, last accessed

May 7, 2018.

2. Hurt, H.H., Ouellet, J.V., and Thom, D.R. (1981). Motorcycle Accident Cause Factors and

Identification of Countermeasures, Vol.1: Technical Report, Traffic Safety Center,

University of California, Berkeley, CA.

3. National Highway Traffic Safety Administration. (2018). “National Automotive Sampling

System (NASS).” (website) National Highway Traffic Safety Administration, Washington,

DC. Available online: https://www.nhtsa.gov/research-data/national-automotive-sampling-

system-nass, last accessed May 7, 2018

4. Federal Highway Administration. (2012). Manual on Uniform Traffic Control Devices for

Streets and Highways, Federal Highway Administration, Washington, DC. Available online:

https://mutcd.fhwa.dot.gov/, last accessed May 7, 2018.

HRDS-20/09-18(WEB)E

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